Develop Reference

Why the permission Manifest.permission.ACCESS_FINE_LOCATION not active the "Location" option?

I have a code that makes location requests for the user, everything works fine as long as the user is already in the "location" mode is active, however, if the "location" mode is not activated in the device notification bar location returns null, I know that when we disable the option the cache of locations is cleared, how could I ask the user to activate the option for q then I request the getLastLocation?
fusedLocationProviderClient.getLastLocation().addOnCompleteListener(new OnCompleteListener<Location>() {
#Override
public void onComplete(#NonNull Task<Location> task) {
localidade = task.getResult();
if(localidade != null){
try {
locFromLatLon = new Geocoder(AddAnuncioActivity.this, Locale.getDefault());
List<Address> addresses = locFromLatLon.getFromLocation(localidade.getLatitude(), localidade.getLongitude(), 1);
Log.i("VALORZAS", addresses.get(0).getCountryName());
} catch (IOException e) {
e.printStackTrace();
}
}else{
// Put some here whenlocation is null -- this happens when the Location option in notification bar of // user is unabled
}
}
});
This only work if the option from the image is enabled, if this option is off, the getResult returns null.
My onResume function:
#Override
protected void onResume() {
super.onResume();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(60000);
locationRequest.setFastestInterval(5000);
LocationCallback locationCallback = new LocationCallback(){
#Override
public void onLocationResult(LocationResult locationResult) {
if (locationResult == null) {
Toast.makeText(getApplicationContext(), "Localidade ainda vazia", Toast.LENGTH_LONG).show();
return;
}
for (Location location : locationResult.getLocations()) {
}
}
};
fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, null);
}

You can try with LocationManager:
final LocationManager manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (!manager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
//Call Alert or use android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS
}
Refer the Documentation

Running location updates in the background

I have the following functions that retrive the current position of the device. My problem is that I am unable to run this Service the background(I tried using Service intent but to no avail).
private LocationRequest mLocationRequest;
private long UPDATE_INTERVAL = 10 * 1000; /* 10 secs */
private long FASTEST_INTERVAL = 2000; /* 2 sec */
protected void startLocationUpdates() {
// Create the location request to start receiving updates
mLocationRequest = new LocationRequest();
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setInterval(UPDATE_INTERVAL);
mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
// Create LocationSettingsRequest object using location request
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
builder.addLocationRequest(mLocationRequest);
LocationSettingsRequest locationSettingsRequest = builder.build();
// Check whether location settings are satisfied
// https://developers.google.com/android/reference/com/google/android/gms/location/SettingsClient
SettingsClient settingsClient = LocationServices.getSettingsClient(this);
settingsClient.checkLocationSettings(locationSettingsRequest);
if(ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION)!=PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS_COARSE_LOCATION)!=PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.ACCESS_FINE_LOCATION},1);
}else{
// locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,0,0,locationListener);
}
// new Google API SDK v11 uses getFusedLocationProviderClient(this)
getFusedLocationProviderClient(this).requestLocationUpdates(mLocationRequest, new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
// do work here
Log.d("test",locationResult.getLastLocation().toString());
onLocationChanged(locationResult.getLastLocation());
}
},
Looper.myLooper());
}
public void onLocationChanged(Location location) {
// New location has now been determined
String msg = "Updated Location: " +
Double.toString(location.getLatitude()) + "," +
Double.toString(location.getLongitude());
Toast.makeText(this, msg, Toast.LENGTH_SHORT).show();
// You can now create a LatLng Object for use with maps
}
public void getLastLocation() {
// Get last known recent location using new Google Play Services SDK (v11+)
FusedLocationProviderClient locationClient = getFusedLocationProviderClient(this);
if(ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION)!=PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS_COARSE_LOCATION)!=PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.ACCESS_FINE_LOCATION},1);
}else{
// locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,0,0,locationListener);
}
locationClient.getLastLocation()
.addOnSuccessListener(new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
// GPS location can be null if GPS is switched off
if (location != null) {
onLocationChanged(location);
}
}
})
.addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception e) {
Log.d("MapDemoActivity", "Error trying to get last GPS location");
e.printStackTrace();
}
});
}
at the moment I start the location update Service trough the startLocationUpdates(); function. I am open to any suggestions as long as they retain the current functionality of the Service. Sorry if the question seems stupid but I am very new to android.

Use like this
if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.M) {
Intent ServiceG = new Intent(context, ClipboardService.class);
context.startService(ServiceG);
} else {
Intent ServiceG = new Intent(context, ClipboardJobService.class);
//context.startService(ServiceG);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
context.startForegroundService(ServiceG);
}else {
context.startService(ServiceG);
}
}

location data null with .getLastLocation() FusedLocationProviderClient

I am getting coordinates with FusedLocationProviderClient in my application on a button click to store into a database. The issue is that when I reboot the phone or the emulator the .getLastLocation() is null and I have to click another time the button i order for this to work. Is there a way to force to get a current position if the value of location from .lastKnownPosition() is null?
// Google fused location client for GPS position
private FusedLocationProviderClient flpc;
// Vars to store GPS info
public Double latitude, longitude;
public Float accuracy;
// Google Fused Client for location
public void getLocation() {
// FusedLocationProviderClient
flpc = LocationServices.getFusedLocationProviderClient(context);
if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
......
return;
}
// Get the latest position from device
Task<Location> task = flpc.getLastLocation();
task.addOnSuccessListener(new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
if(location!=null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
accuracy = location.getAccuracy();
}
}
});
}
In my button handler I call getLocation() and use latitude, longitude and accuracy to store to the database.
Any help appreciated!

When getLastLocation() is null, you need to make a LocationRequest
private LocationRequest locationRequest;
private LocationCallback locationCallback;
...
locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(20 * 1000);
locationCallback = new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
if (locationResult == null) {
return;
}
for (Location location : locationResult.getLocations()) {
if (location != null) {
wayLatitude = location.getLatitude();
wayLongitude = location.getLongitude();
txtLocation.setText(String.format(Locale.US, "%s -- %s", wayLatitude, wayLongitude));
}
}
}
};
mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, Looper.getMainLooper())
If you don't need continuous updates, you can remove the request once you've received it.
mFusedLocationClient.removeLocationUpdates(locationCallback);
More info here: https://medium.com/#droidbyme/get-current-location-using-fusedlocationproviderclient-in-android-cb7ebf5ab88e

When the phone is rebooted the cached last location is lost so if you didnt open up an app that uses GPS like google maps or something then there will be no last location.
There never has to be a location returned to you, you should always assume it could be null.
If you want to get location, you just need to use LocationCallback as #tenprint said in this thread.
Refer this links
Android get location is null after phone reboot

FusedLocationProviderClient gives different location sometimes

public void getDeviceLocation() {
fusedLocationClient = LocationServices.getFusedLocationProviderClient(getMvpView().getActivity());
settingsClient = LocationServices.getSettingsClient(getMvpView().getActivity());
createLocationCallback();
createLocationRequest();
buildLocationSettingsRequest();
startLocationUpdates();
}
private void createLocationRequest() {
locationRequest = new LocationRequest();
locationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
locationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
private void createLocationCallback() {
getMvpView().showProgressDialog();
locationCallback = new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
super.onLocationResult(locationResult);
Location currentLocation = locationResult.getLastLocation();
getMvpView().showSelectedAddress(getAddressFromLatLng(currentLocation.getLatitude(), currentLocation.getLongitude()));
fusedLocationClient.removeLocationUpdates(locationCallback);
getMvpView().hideProgressDialog();
}
};
}
private void buildLocationSettingsRequest() {
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
builder.addLocationRequest(locationRequest);
locationSettingsRequest = builder.build();
}
private void startLocationUpdates() {
settingsClient.checkLocationSettings(locationSettingsRequest)
.addOnSuccessListener(getMvpView().getActivity(), locationSettingsResponse -> {
if (ActivityCompat.checkSelfPermission(getMvpView().getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getMvpView().getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
fusedLocationClient.requestLocationUpdates(locationRequest,
locationCallback, Looper.myLooper());
}).addOnFailureListener(getMvpView().getActivity(), e -> {
getMvpView().hideProgressDialog();
getMvpView().showErrorToast(R.string.please_enable_location);
});
}
#SuppressLint("MissingPermission")
private void startLocationUpdates() {
settingsClient.checkLocationSettings(locationSettingsRequest)
.addOnSuccessListener(getMvpView().getActivity(), locationSettingsResponse -> {
fusedLocationClient.requestLocationUpdates(locationRequest,
locationCallback, Looper.myLooper());
}).addOnFailureListener(getMvpView().getActivity(), e -> {
getMvpView().hideProgressDialog();
getMvpView().showErrorToast(R.string.please_enable_location);
});
}
private String getAddressFromLatLng(double latitude, double longitude) {
Geocoder geocoder = new Geocoder(getMvpView().getActivity(), Locale.getDefault());
List<Address> addresses = null;
try {
addresses = geocoder.getFromLocation(
latitude,
longitude,
1);
} catch (IOException e) {
e.printStackTrace();
}
Address address = addresses.get(0);
StringBuilder addressStringBuilder = new StringBuilder();
for (int i = 0; i <= address.getMaxAddressLineIndex(); i++) {
addressStringBuilder.append(address.getAddressLine(i));
}
return addressStringBuilder.toString();
}
I have converted the lat, lng to address text but after i query again for location the address changes even i have not moved from my current location, enabled accuracy in phone settings too. The issue is when i always query it should give me the same location address if my lat, lng postion is not changed.

FusedLocationProviderClient means combining gps and google-translating-received-wlan-cellphone-tower-signals-to-lat-lon.
The google-translating-received-wlan-cellphone-tower-signals-to-lat-lon is an inexact heuristics that among other factors depends to which cellphone-tower your handy is connected to (and where google has lat/lon for each tower) and how stronge the strongest 3 cellphonetowers are.
If your cellphone changes it's cellphone-tower-connection then for googl-s algorithm your phone position has changed.
If your cellphone can receive more than 3 cellphone towers the strongest 3 cellphonetowers will also change depending how much trafic each celltower has.
A gps-receiver costs a lot of energy. When gps-energy-optimisation is enabled then there may be also gps-precision issuses causing the fused location to jump.
I learned this the hard way when doing geocaching for the first time with my brand new cellpone and wondered why my own position jumped in the map

My current location always returns null. How can I fix this?

I am trying to find my current location for an android project. When the application is loaded my current location is always null. I have set up the permissions in the manifest etc. When I find the current location I intend to use the coordinates to find distances to other locations on the map. My code snippet is below. Why do I always get a null value?
locMan = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria crit = new Criteria();
towers = locMan.getBestProvider(crit, false);
location = locMan.getLastKnownLocation(towers);
if (location != null) {
System.out.println("Location is not null!");
lat = (int) (location.getLatitude() *1E6);
longi = (int) (location.getLongitude() * 1E6);
GeoPoint ourLocation = new GeoPoint(lati, longi);
OverlayItem overlayItem = new OverlayItem(ourLocation, "1st String",
"2nd String");
CustomPinpoint custom = new CustomPinpoint(d, MainMap.this);
custom.insertPinpoint(overlayItem);
overlayList.add(custom);
overlayList.clear();
} else {
System.out.println("Location is null! " + towers);
Toast.makeText(MainMap.this, "Couldn't get provider",Toast.LENGTH_SHORT)
.show();
}

getLastKnownLocation() uses the location(s) previously found by other applications. if no application has done this, then getLastKnownLocation() will return null.
One thing you can do to your code to have a better chance at getting as last known location- iterate over all of the enabled providers, not just the best provider. For example,
private Location getLastKnownLocation() {
List<String> providers = mLocationManager.getProviders(true);
Location bestLocation = null;
for (String provider : providers) {
Location l = mLocationManager.getLastKnownLocation(provider);
ALog.d("last known location, provider: %s, location: %s", provider,
l);
if (l == null) {
continue;
}
if (bestLocation == null
|| l.getAccuracy() < bestLocation.getAccuracy()) {
ALog.d("found best last known location: %s", l);
bestLocation = l;
}
}
if (bestLocation == null) {
return null;
}
return bestLocation;
}
If your app can't deal without having a location, and if there's no last known location, you will need to listen for location updates. You can take a look at this class for an example,
https://github.com/farble1670/autobright/blob/master/src/org/jtb/autobright/EventService.java
See the method onStartCommand(), where it checks if the network provider is enabled. If not, it uses last known location. If it is enabled, it registers to receive location updates.

if u find current location of devices the use following method in main class
public void find_Location(Context con) {
Log.d("Find Location", "in find_location");
this.con = con;
String location_context = Context.LOCATION_SERVICE;
locationManager = (LocationManager) con.getSystemService(location_context);
List<String> providers = locationManager.getProviders(true);
for (String provider : providers) {
locationManager.requestLocationUpdates(provider, 1000, 0,
new LocationListener() {
public void onLocationChanged(Location location) {}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status,
Bundle extras) {}
});
Location location = locationManager.getLastKnownLocation(provider);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
addr = ConvertPointToLocation(latitude, longitude);
String temp_c = SendToUrl(addr);
}
}
}
And Add User Permission method in your manifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

Try this this will not give you null current location
class GetLastLocation extends TimerTask {
LocationManager mlocManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListenerTmp = new CustomLocationListener();
private final Handler mLocHandler;
public GetLastLocation(Handler mLocHandler) {
this.mLocHandler = mLocHandler;
}
#Override
public void run() {
timer.cancel();
mlocManager.removeUpdates(mlocListenerTmp);
Location location = mlocManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
{
if (mlocListenerTmp != null) {
mlocManager.removeUpdates(mlocListenerTmp);
}
currentLocation = location;
}
if (location != null) {
String message = String.format(
"Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude());
Log.d("loc", " :" + message);
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", true);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
} else {
Log.d(
"loc",
":No GPS or network signal please fill the location manually!");
location = mlocManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
currentLocation = location;
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", true);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
} else {
Bundle b = new Bundle();
{
b.putBoolean("locationRetrieved", false);
{
Message msg = Message.obtain();
{
msg.setData(b);
mLocHandler.sendMessage(msg);
}
}
}
}
}
}
}
call it like this
timer.schedule(new GetLastLocation(mLocHandler), 3000);
and the customLocationclass is as follows
public class CustomLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location loc) {
loc.getLatitude();
loc.getLongitude();
currentLocation = loc;
String Text = "My current location is: " + "Latitud = "
+ loc.getLatitude() + "Longitud = " + loc.getLongitude();
Log.d("loc", "onLocationChanged" + Text);
}
#Override
public void onProviderDisabled(String provider) {}
#Override
public void onProviderEnabled(String provider) {}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {}
}

If you are trying it out in a marshmallow device, try enabling location permission for your app manually.

turn on your GPS by using below method. it helps you to show your current location without any ERROR. call it in onCreate
public void displayLocationSettingsRequest(Context context, int requestCode) {
GoogleApiClient googleApiClient = new GoogleApiClient.Builder(context)
.addApi(LocationServices.API).build();
googleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(10000);
locationRequest.setFastestInterval(10000 / 2);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(locationRequest);
builder.setAlwaysShow(true);
PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(result1 -> {
final Status status = result1.getStatus();
if (status.getStatusCode() == LocationSettingsStatusCodes.RESOLUTION_REQUIRED)
try {
status.startResolutionForResult((Activity) context, requestCode);
} catch (IntentSender.SendIntentException ignored) {
}
});

If you are getting a null error with your provider list, change...
List<String> providers = mLocationManager.getProviders(true);
to...
List<String> providers = locationManager.getAllProviders();
This worked for me, and make sure that you have the following in your AndroidManifest.xml file...
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

Have you tried reversing the code? For example, if(location==null) then print that location is null, and else print location is not null. I got that problem once before and that seemed to have fixed it (i don't know why). Try that.
If that doesn't work, perhaps the google maps API is returning the null value, in which case its a problem with the GM-API or with the call method. Any of these could be the problem.